Tomorrow is the spring equinox - the first day of astronomical spring, following the start of meteorological spring on March 1 - and temperatures will hit 21C (70F).
On March 20, 2025, Britain is expected to experience its warmest day of the year so far, potentially reaching 21C (70F), marking the first day of astronomical spring. Temperatures are predicted to rise from 17C in London today, following colder temperatures earlier in the week. A Met Office meteorologist forecasts continued sunshine and warm weather for the next few days, with Thursday being the peak of the warmth for most places.
